Bow-spring for eyeglasses.



m..7s0,4 50. I I PATENTED'J-UNE 9,1903.

I. FOX. I BOW SPRING FOR EYEGLASSES. APPLICATION TIL ED NOV. 13, 1902.

10 MODEL.

lNVENTOR:

WITNESSES:

Patented June 9, 1903.

PATENT OFFICE.

WAN FOX, or LANSDOWNE, PENNSYLVANIA.

BOW-SPRING FOR EYEGLASSES.

SPECIFICATION forming part of Letters Patent No. 731,450, dated June 9,1903.

To all whom it may concern:

Be it known that I, IVAN FOX, a citizen of the United States, residingat Lansdowne, county of Delaware, and State of Pennsylvania, haveinvented certain new and useful Improvements in Bow-Springs forEyeglasses, of which the following is a specification.

In its generic aspect, this invention relates to eye glass frames,andspecifically to the bow eipal objects sought after in the constructionof eye glass frames is to secure the requisite strength by the use ofthe smallest possible quantity of metal.

Totheseends'Ihave utilized, in theconstruction of the bow spring for eyeglassframesat well-known fact in physical science, namely, that a givenamount of metal formed into a tube or which is of arcuate shape intransverse sectiou,that is,curved transversely,subject to certainlimitations, possesses greater strength than the same amount of metal ina solid condition and which is in the form of a solid cylinder, or whichhas a transverse section of rectangular or similar outline.

My invention consists of a bow spring for eye glasses, which is eitherof tubular or transversely curved outline. For a clearer understandingof my invention, reference is to be had to the accompanying drawings, inwhich Figure 1 is a rear elevation of a pair of eye glasses providedwith a tubular bow spring.

Figure 2 is .a side elevation of the bow spring shown in Figure 1, thelenses and other parts being omitted.

Figures 3 and 4 are bottom plan and transverse sectionalviews,respectively, of the bow spring shown in Figure 2.

Application filed November 13, 1902. Serial No. 151,145. (No-model.)

Figure 5 is a side elevation of a modified form of how spring. 1

Figures 6 and 7 are bottom plan and transverse sectional views,respectively, of the bow spring shown in Figure 51 I regard the form ofbow spring which is illustrated in Figures 1 to 4:, inclusive, as beingpreferable to that which is illustrated in Figures 5 to 7, inclusive. 3In Figure 1,1 have illustrated a pair of eye glasses in which the'lensesl are provided with posts or standards 2, and the nose guard 3, ofconstruction identical with that shown in my patent numbered 695,681.

4 designates a bow spring having a tubular portion 5, and arcuate shapedportions 6, which are located upon the opposite sides, respectively, ofthe tubular portion 5. It

will be observed that the arcuate shaped portions 6 are approximatelysemi-tubular in transverse scclionahoutline, and it is to be understoodthat these'arcuate shaped portions .6 may be either greater or less thana semitnbe. The opposite ends of the bow spring are flattened outasshown at 7, the flattened out portions being provided with an opening8, as shown in Figure 4c. The purpose of this flattened out portion andof the opening 8 is to provide means whereby the'bow spring may besecured to the posts or standards 2 and whereby the lenses 1 may besecured together.

In Figures 5 to 7 I haveillustrated a modified construction of howspring in which the said spring is are shaped and approximatelysemi-tubular throughout substantially its entire length.

.The opposite ends of the said spring are, however, flattened out asshown at 7, and are provided with openings 8 for the same purpose asthat stated with respect to the construction shown in Figures 1 to 4.

While I have illustrated the bow spring in Figures 5 to 7, and theportions 6 in Figures 1 to 4, as having a transverse section ofapproximately semi tu'hular outline, it is obvious that advantageousresults maybe secured by the use of a spring, the transverse sectionaloutline of which forms a smaller sectional portion of a tube.

In the manufacture of the bow spring herein described, I prefer to curveor bend transversely, by the use of any suitable means, a flat strip ofmetal of any desired length, so that-a transverse section thereof is ofarcuate shape in outline, after which I divide it up into shortsections, each section being of suflicient length to form a bow spring.The said sections are bent longitudinally to form bow springs, such asare illustrated in Figures 5 to 7, after which, if desired, the centraltubular portion illustrated in Figures 1 to 4, inclusive, of thedrawings, is formed in any suitable manner, as by means of a die.

The opposite end portions of the said bow spring may be flattened out ina manner most convenient, and it is obvious that the said flattened endsmay be slightly curved transversely without in any way interfering withtheir attachment to the posts or standards 2. It is obvious that thetubular portion 5 may be made ofgreater or less length, as desired,without departing in any way from the spirit of this invention.

Having thus described my invention, I claim A 1. A bow spring for eyeglasses having a transverse section of arcuate shape or outline, andhaving its opposite ends provided with suitable means for attaching itto the lenses of the eye glasses.

2. A bow spring for eye glasses comprising a portion, a transversesection of which is of arcuate shape, and the said how spring having itsopposite ends flattened for the purpose set forth.

3. A bow spring for eye glasses, comprising a semi-tubular portion andflattened end portions for the purpose set forth.

4:. A bow spring for eye glasses, comprising a tubular portion andflattened end portions for the purpose set forth.

5. A bow spring for eye glasses comprising a tubular portion, portionshaving a transverse section of arcuate shape in outline, and flattenedend portions as set forth.

6. A bow spring for eye glasses consisting of a thin strip of metal benttransversely and longitudinally, and having relatively flattened endportions, as described.

7. A bow spring for eye glasses, comprising a tubular portion,semi-tubular portions, and flattened end portions, for the purposedescribed.

8. A bow spring for eye glasses, consisting of a thin metallic strip,bent transversely and longitudinally, the central portion of said bowspring being formed into a tube and the portions thereof upon oppositesides,

respectively, of said tube being curved transversely to form portions ofarcuate shape in transverse section, and flattened portions at theopposite ends of said spring, for the purpose described.

9. A bow spring for eye glasses, comprising a tubular portion, atransversely curved portion located on one side of said tubular portion,and another transversely curved portion located on the other side ofsaid tubular portion, the said transversely curved portions being ofarcuate shape in transverse section, and flattened end portions at theopposite ends of said spring,substantially as described.

10. A bow spring for eye glasses consisting of a thin strip of suitablematerial bent transversely and longitudinally, substantially asdescribed.

In testimony that I claim the foregoing as myinventionlhave hereuntosigned myname this 11th day of November, A. D. 1902.

IVAN FOX.

In presence'of v THOS. K. LANCASTER, L. KLEINFELDER.

